Express the terms of the following sequence by giving an explicit formula. -1/2,-1 1/2, -21/2, -3 1/2,.. A. an = 1/2 - n, where n = 1, 2, 3, 4, ...
B. an = 2n, where n = 1, 2, 3, 4, ..
C. an = 1/2 - 2n, where n = 1, 2, 3, 4, ...
D. an = 1/2n , where n = 1, 2, 3, 4, ...​

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads

1/3

step-by-step explanation:

to find this, you can divide 12 by 4 which is 3 or you can multiply 4 until you reach 12 (4x3=12). both should give you 3, meaning theres three times less bananas than there are oranges.

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°