a.)If a=9*23 and b=9*124, what is the value of b-a?

Do the multiplication. Then do the subtraction.

b.)By how much does the product of 8 and 25 exceed the product of 15 and 10?

Do the multiplication. Then do the subtraction.

c.)How many containers, each holding 16 fluid ounces of juice, are needed to hold 5 quarts of juic? (1 quart=32 fluid ounces)

How many fluid ounces are in one quart? Then how many fluid ounces are in five quarts? (Hint: Multiply.)

How many sixteen-fluid-ounce portions can fit into this total value? (Hint: Divide.)

d.)If the current reading of a truck's odometer reading is 31,983 miles, what is the smallest number of miles that the truck must travel before the odometer displays four digits that are the same?

Work through the various options, picking the digit to be repeated, and seeing what this gives you. For instance, if zero is to be repeated four times, then the next value is 40,000, more than eight thousand miles. On the other hand, if two is to be repeated, then the next value is 32,222, less than two hundred miles. If four is to be repeated, you could have 34,444, 40,444, 41,444, 42,444,... 44,044, 44,144, 44,244,... , and so forth.

Work through the options, and then figure out which one is best.