I have like two more I don't understand, I'm in 4th and on my sisters account and I was sick while learning this so I don't know how please help will mark brainliest

Find the sum of the first 8 terms of the following sequence. round to the nearest hundredth if necessary.

Solve for x -2.3(r - 1.2 ) = -9.66 enter you answer as decimal.

Ametal rod needs to be 9 feet and 5.5 inches in length. the sections of the poles being used are each 1 foot and 10.5 inches long. how many 1ft 10.5in sections would be needed to complete the 9ft 5.5in metal rod? and how many inches of material will be left?