I have finished the assignment

MathUtilities.java

      * @return sum of `baseValue` and `difference`
      */
     public Integer add(int baseValue, int difference) {
-        return null;
+        int sisterAct = (baseValue + difference);
+        return sisterAct;
     }
 
     /**
      * @return sum of `baseValue` and `difference`
      */
     public Long add(long baseValue, long difference) {
-        return null;
+        long newStuff = (baseValue + difference);
+        return newStuff;
     }
 
     /**
      * @return sum of `baseValue` and `difference`
      */
     public Short add(short baseValue, short difference) {
-        return null;
+        short hello = (short)(baseValue + difference);
+        return hello;
     }
 
     /**
      * @return sum of `baseValue` and `difference`
      */
     public Byte add(byte baseValue, byte difference) {
-        return null;
+        byte newStuff = (byte)(baseValue + difference);
+        return newStuff;
     }
 
     /**
      * @return sum of `baseValue` and `difference`
      */
     public Float add(float baseValue, float difference) {
-        return null;
+        float newStuff = (float)(baseValue + difference);
+        return newStuff;
     }
 
     /**
      * @return sum of `baseValue` and `difference`
      */
     public Double add(double baseValue, double difference) {
-        return null;
+       double variableForDouble = (double)(baseValue + difference);
+       return variableForDouble;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Integer subtract(int baseValue, int difference) {
-        return null;
+       int newVar = (int)(baseValue - difference);
+        return newVar;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Long subtract(long baseValue, long difference) {
-        return null;
+        long sisterAct = (long)(baseValue - difference);
+        return sisterAct;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Short subtract(short baseValue, short difference) {
-        return null;
+        short newVar = (short)(baseValue - difference);
+        return newVar;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Byte subtract(byte baseValue, byte difference) {
-        return null;
+        byte newVar = (byte)(baseValue - difference);
+        return newVar;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Float subtract(float baseValue, float difference) {
-        return null;
+        float newVar = (baseValue -difference);
+         return newVar;
     }
 
     /**
      * @return difference between `baseValue` and `difference`
      */
     public Double subtract(double baseValue, double difference) {
-        return null;
+        double newVar = (baseValue - difference);
+        return newVar;
     }
 
 
      * @return division of `dividend` by `divisor
      */
     public Integer divide(int dividend, int divisor) {
-        return null;
+        int result = (dividend / divisor);
+        return result;
     }
 
     /**
      * @return division of `dividend` by `divisor
      */
     public Long divide(long dividend, long divisor) {
-        return null;
+        long result = (dividend / divisor);
+        return result;
     }
 
     /**
      * @return division of `dividend` by `divisor
      */
     public Short divide(short dividend, short divisor) {
-        return null;
+        short newStuff = (short)(dividend/divisor);
+        return newStuff;
     }
 
     /**
      * @return division of `dividend` by `divisor
      */
     public Byte divide(byte dividend, byte divisor) {
-        return null;
+        byte newStuff = (byte) (dividend/divisor);
+        return newStuff;
     }
 
     /**
      * @return division of `dividend` by `divisor
      */
     public Float divide(float dividend, float divisor) {
-        return null;
+        float newVar = (dividend/divisor);
+        return newVar;
     }
 
     /**
      * @return division of `dividend` by `divisor
      */
     public Double divide(double dividend, double divisor) {
-        return null;
+        double newVar = (double)(dividend/divisor);
+        return newVar;
     }
 
 
      * @return product of `multiplicand` by `multiplier`
      */
     public Integer multiply(int multiplicand, int multiplier) {
-        return null;
+        int newVar = (multiplicand*multiplier);
+        return newVar;
     }
 
     /**
      * @return product of `multiplicand` by `multiplier`
      */
     public Long multiply(long multiplicand, long multiplier) {
-        return null;
+        long newVar = (multiplicand*multiplier);
+        return newVar;
     }
 
     /**
      * @return product of `multiplicand` by `multiplier`
      */
     public Short multiply(short multiplicand, short multiplier) {
-        return null;
+        short newVar = (short)(multiplicand*multiplier);
+        return newVar;
     }
     /**
      * @param multiplicand value to be multiplied
      * @return product of `multiplicand` by `multiplier`
      */
     public Byte multiply(byte multiplicand, byte multiplier) {
-        return null;
+        byte newVar = (byte)(multiplicand*multiplier);
+        return newVar;
     }
 
     /**
      * @return product of `multiplicand` by `multiplier`
      */
     public Float multiply(float multiplicand, float multiplier) {
-        return null;
+        float newVar = (multiplicand*multiplier);
+        return newVar;
     }
 
     /**
      * @return product of `multiplicand` by `multiplier`
      */
     public Double multiply(double multiplicand, double multiplier) {
-        return null;
+        double newVar = (multiplicand*multiplier);
+        return newVar;
     }
 
 
       * @return true
      */
     public Boolean returnTrue() {
-        return null;
+        return true;
     }
 
     /**
      * @return false
      */
     public Boolean returnFalse() {
-        return null;
+        return false;
     }
 
 }

PredicateUtilities.java

      * @return true if `x` is greater than `y`
      */
     public Boolean isGreaterThan(int x, int y) {
-        return null;
+        if (x > y) {
+        return true;
+    } else{
+        return false;
+    }
     }
 
     /**
      * @return true if `x` is less than `y`
      */
     public Boolean isLessThan(int x, int y) {
-        return null;
+        if (x < y) {
+        return true;
+    } else {
+        return false;
+    }
     }
 
     /**
      * @return true if `x` is greater than or equal to `y`
      */
     public Boolean isGreaterThanOrEqualTo(int x, int y) {
-        return null;
+        if (x >= y) {
+        return true;
+    } else {
+        return false;
+    }
     }
 
     /**
      * @return true if `x` is less than or equal to `y`
      */
     public Boolean isLessThanOrEqualTo(int x, int y) {
-        return null;
+        if (x <= y) {
+        return true;
+    } else {
+        return false;
     }
+}
 }

StringUtilities.java

      * @return `Hello World` as a string
      */
     public static String getHelloWorld() {
-        return null;
+        String word = "Hello World";
+            return word;
+        
     }
 
     /**
      * @return the concatenation of two strings, `firstSegment`, and `secondSegment`
      */
     public static String concatenation(String firstSegment, String secondSegment){
-        return null;
+       String word = firstSegment + secondSegment;
+       return word;
     }
 
     /**
      * @return the concatenation of an integer, `firstSegment`, and a String, `secondSegment`
      */
     public static String concatenation(int firstSegment, String secondSegment){
-        return null;
+        String differentVar = firstSegment + secondSegment;
+        return differentVar;
     }
 
     /**
      * @return the first 3 characters of `input`
      */
     public static String getPrefix(String input){
-        return null;
+      String newString = new String();
+      newString = input.substring(0, 3);
+      return newString;
     }
 
     /**
      * @return the last 3 characters of `input`
      */
     public static String getSuffix(String input){
-        return null;
+        String newString = new String();
+        newString = input.substring(input.length() - 3);
+       return newString;
     }
 
     /**
      * @return the equivalence of two strings, `inputValue` and `comparableValue`
      */
     public static Boolean compareTwoStrings(String inputValue, String comparableValue){
-        return null;
-    }
+        if (inputValue.equals(comparableValue)){
+            return true;
+        } else {
+            } return false;
+        }
+       
+   
 
     /**
      * @param inputValue the value input from user
      * @return the middle character of `inputValue`
      */
     public static Character getMiddleCharacter(String inputValue){
-        return null;
+        int length =  inputValue.length();
+        if (length % 2 == 0){
+            return inputValue.charAt((length/2) -1);
+    }else{
+        return inputValue.charAt((length -1)/2);
     }
+}
 
     /**
      * @param spaceDelimitedString a string, representative of a sentence, containing spaces
      * @return the first sequence of characters
      */
     public static String getFirstWord(String spaceDelimitedString){
-        return null;
+        String[] dope = spaceDelimitedString.split(" ");
+            return dope[0];
+        
     }
 
     /**
      * @return the second word of a string delimited by spaces.
      */
     public static String getSecondWord(String spaceDelimitedString){
-        return null;
+        String[] yerp = spaceDelimitedString.split(" ",3);
+        return yerp[1];
     }
 
     /**
      * @return an identical string with characters in reverse order.
      */
     public static String reverse(String stringToReverse){
-        return null;
+       StringBuilder reversedStringNow = new StringBuilder(stringToReverse);
+        
+        return reversedStringNow.reverse().toString();
+       
     }
 }

package.bluej

 #BlueJ package file
-editor.fx.0.height=0
-editor.fx.0.width=0
-editor.fx.0.x=0
-editor.fx.0.y=0
-objectbench.height=129
+editor.fx.0.height=722
+editor.fx.0.width=800
+editor.fx.0.x=320
+editor.fx.0.y=53
+objectbench.height=128
 objectbench.width=1171
 package.divider.horizontal=0.6
-package.divider.vertical=0.7490774907749077
-package.editor.height=399
+package.divider.vertical=0.7509225092250923
+package.editor.height=400
 package.editor.width=1069
 package.editor.x=59
 package.editor.y=63