Really need help on these questions

The boiling point of water drops by about one degree centigrade for every 300 meters (or 1,000 feet) of altitude. Improve the program of Exercise E5.11 to allow the user to supply the altitude in meters or feet. Add error handling to Exercise E5.12. If the user does not enter a number when expected, or provides an invalid unit for the altitude, print an error message and end the program. When two points in time are compared, each given as hours (in military time, ranging from 0 and 23) and minutes, the following pseudocode determines which comes first. if hour1 = 21 If season is "Winter", season= "Spring" Else if season is "Spring", season= "Summer" Else if season is "Summer", season = "Fall" Else season = "Winter" Write a program that prompts the user for a month and day and then prints the season, as determined by this algorithm. Use a class Date with a method getSeason. Write a program that translates a letter grade into a number grade. Letter grades are A, B, C, D, and F, possibly followed by + or -. Their numeric values are 4, 3, 2, 1, and 0. There is no F+ or F-. A+ increases the numeric value by 0.3, a-decreases it by 0.3. However, an A+ has value 4.0. Enter a letter grade: B- The numeric value is 2.7. Use a class Grade with a method getNumericGrade. The boiling point of water drops by about one degree centigrade for every 300 meters (or 1,000 feet) of altitude. Improve the program of Exercise E5.11 to allow the user to supply the altitude in meters or feet. Add error handling to Exercise E5.12. If the user does not enter a number when expected, or provides an invalid unit for the altitude, print an error message and end the program. When two points in time are compared, each given as hours (in military time, ranging from 0 and 23) and minutes, the following pseudocode determines which comes first. if hour1 = 21 If season is "Winter", season= "Spring" Else if season is "Spring", season= "Summer" Else if season is "Summer", season = "Fall" Else season = "Winter" Write a program that prompts the user for a month and day and then prints the season, as determined by this algorithm. Use a class Date with a method getSeason. Write a program that translates a letter grade into a number grade. Letter grades are A, B, C, D, and F, possibly followed by + or -. Their numeric values are 4, 3, 2, 1, and 0. There is no F+ or F-. A+ increases the numeric value by 0.3, a-decreases it by 0.3. However, an A+ has value 4.0. Enter a letter grade: B- The numeric value is 2.7. Use a class Grade with a method getNumericGrade