Find the sum of the following vectors A=3i-12j and B=4i+7j

(I). The sum of the vectors is (7i-5j).

(II). The sum of the vectors is (8i+7j).

Explanation:

Given that,

(I). Vector A

Vector B

Suppose, (II). Vector A

Vector B

(I). We need to calculate the sum of the vectors

Using formula of sum

Where,

(II). We need to calculate the sum of the vectors

Using formula of sum

Put the value into the formula

Hence, The sum of the vectors is (7i-5j).

The sum of the vectors is (8i+7j).

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.