What is 88888+888888888

Describe all the numbers that when rounded to the nearest thousand are 645,000

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6