The fourth term in an arithmetic sequence is 18 and the seventh term is 39. If the first term is a1 , which is an equation for the nth term of this sequence?

Idont get this question can someone me solve it? ** the distance light travels in one second (1 light second) is about 1.86 ×10^5 mi. saturn is about 475 light-seconds from the sun. about how many miles from the sun is saturn..my guess is 8.83* 10^7 you so much

Which of the following is the equation that says that the product of a number and ten is equal to 20 percent of that number ? a) 10n= 2.0n b) 10+n=.20n c) n+ .20n=10 d) 10n=0.20n

Find the magnitude, correct to two decimal places, made by each of the following with positive direction of the x axis a) y= x the answer is 45° but i don’t know how