If a is a rational number and b is a rational number, then the product ab must be a) rational. b) imaginary. c) an integer. d) irrational.

A. Rational

Step-by-step explanation:

You cant make imaginary numbers by multiplication of rational numbers.

Since rational numbers includes fractions, a multiplication of rational numbers wont always mean a integer.

You cant make an irrational number by multiplication of rational.

Our answer must be rational.

answer:  

step-by-step explanation:

here x represents the height of the pole,

and, the height of the shadow of the pole is 12 feet.

also, the angle of elevation from the top of the pole is 40°,

therefore,

by the low of sine,

which is the required equation for finding the value of x,

9 x 8 divided by (5-3)=36