7. Alice wants to calculate the total cost for a dress. The dress costs $53.99
and sales tax is 7%. Which expression represents how she could
calculate the total cost?
A 53.99(0.07)
B. 53.99(0.7)
C. 53.99(1.07)
D. 53.99(1.7)

What is the value of x in the figure below? if necessary, round your answer to the nearest tenth of a unit. 12 d 4 b оа. 3.1 ов. 6.9 ос. 4 od. 12

Can some one explain how to slove specifically, what is the value of x? 0.9(x+1.4)-2.3+0.1x=1.6 enter the answer as a decimal in the box. x= ?

Suppose a laboratory has a 30 g sample of polonium-210. the half-life of polonium-210 is about 138 days how many half-lives of polonium-210 occur in 1104 days? how much polonium is in the sample 1104 days later? 9; 0.06 g 8; 0.12 g 8; 2,070 g