Simplify the expression:
- 3d + -9d + 5d

The spotter on the ground is standing beneath the safety net. what is his distance from the base of the platform, to the nearest meter? 3 meters, 2 meters, 4 meters, 1 meter?

Ageologist had two rocks on a scale that weighed 4.6 kilograms together. rock a was 0.5 of the total weight. how much did rock a weigh?

Aright triangle has an area of 21 m2. the dimensions of the triangle are increased by a scale factor of 4. what is the area of the new triangle