I need help with 20 and 21 please!

20.(10) I need to determine a business's value (a number value), which is one of my in the business rating levels. Rating levels can be A or B or C or D where business's value (a number value), which is one of many attributes used levels can be A or B or C or D where a value used in the calculations: for an A rating, rate level is 90. B = 80. C-60, D-40. Write the code to determine the RATE (90, 80, 60 or 40) using a switch statement. Assign to RATE one of the four values. cin>>letterRate; switch( ) 21.(10) I am buying a big truck. I need to know the salesman commission for sailing the truck which varies based on the truck price. If the truck price is below $75,000, his commission is 5.7% and of over $75,000 is commission is 6.2%. Given the following, write the code to compute and print the salesman commission to two decimal places after the decimal point. Infile >> TruckPrice