7.Which of the following does NOT properly use the properties of exponents? please help 1.4^3 * 4^4 * 4^2 = 4^9
2.7^3/7^8 = 7^5
3.8^0 * 5^1 * 3^0 = 5
4.(5^2)^2 * (5^1)^5 = 5^

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Me. i can't figure out this question. give an explanation too. .

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.