The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars

7t^2 + 3t + 6

Step-by-step explanation:

The computation of the expression is shown below:

The function describes the manufacturing cost of product A.

a(t) = 5t + 2

Likewise for product B, the manufacturing cost function is

b(t) = 7t^2 - 2t + 4

So if we combined these two, the equation would be presented below

= a(t) + b(t)

= 5t + 2 + 7t^2 - 2t + 4

= 7t^2 + 3t + 6

Hence, the correct option is D

b. an equilateral triangle inscribed in a circle

step-by-step explanation:

we are given the figure of two circles having a triangle inside.

now, we know that,

"when a figure is lying inside an another figure, then the outside figure is known as circumscribed figure and the figure lying inside is referred to as the inscribed figure".

as we see that, the circles are containing the triangle completely.

thus, the circles are the circumscribed figures and the triangle is the inscribed figure.

hence, we get, 'an equilateral triangle is inscribed in a circle'.