Pls try to give it as soon as possible ​

I'm having a hard time with this, I keep confusing myself but hopefully this example will help at least to get an idea:

"12 cm

Explanation:

We're pouring 12 litres of water into a container that is 40cm long and 25cm wide. Let's see how big the bottom of the container is:

40cm×25cm=1000cm2

1 litre of water fills 1000cm3, and so it would rise 1 cm (we divide the volume of the water by the surface area to arrive at the height):

1000cm31000cm2=1cm

12 litres of water can then be seen to rise 12 cm:

12×1000cm31000cm2=12cm"

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.

its an acute right triangle

step-by-step explanation: