If gravity causes black holes, then what is the initial cause of black holes? Answer choices: - energy - gravity - heat - photons - mechanical - sun's heat - cracking - Smoking
gravity
------
If deepening rivers cause the loss of topsoil, then deepening rivers cause? Answer choices: - relocation - the loss of topsoil - Plant growth is reduced - to move people - Physical weathering - forest is destroyed - Water expanding - water conservation
the loss of topsoil
------
If being outside is a good way to get vitamin D, then what is a health benefit you receive for being outside? Answer choices: - Relieve pain - staying warm - exercise - inactive - vitamin D - air cools - layers of fat - sweating
vitamin D
------
If high temperatures can cause dioxins, then what can high temperatures cause? Answer choices: - symptoms - dioxins - Rise - Pollution - anemia - Allergies - disease - sweating
dioxins
------