1.what is the simplified form of each expression?

7x^–8 × 6x^3

a. 42/x^5
b. 1/42x^5
c. 42x^11
d. 13x^–5

(–2x8) · 3y9 · 2x4

a. 3x^12y^9
b. –12x^72y^9
c. –12xy^21
d. –12x^y^9

2. find the simplified form of the expression. give your answer in scientific notation.

(8 x 10^7) (7 x 10^4)

a. 1.5 × 10^12
b. 5.6 × 10^12
c. 1.5 x 10^29
d. 5.6 x 10^29

(7 × 10^–4)(9 × 10^–10)

a. 6.3 × 10^–13
b. 63 × 10^–13
c. 6.3 × 10^–15
d. 6.3 × 10^–16

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. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

If (x-2) 2= 49, then x could be a. -9 b. -7 c.- 2 d. 5 e.9

Recall that the owner of a local health food store recently started a new ad campaign to attract more business and wants to know if average daily sales have increased. historically average daily sales were approximately $2,700. the upper bound of the 95% range of likely sample means for this one-sided test is approximately $2,843.44. if the owner took a random sample of forty-five days and found that daily average sales were now $2,984, what can she conclude at the 95% confidence level?