For which of these questions could a testable hypothesis be developed? Check all that apply. Do children’s heart rates increase at the same speed when walking uphill?
Is experimenting with moldy bread more fun than experimenting with yogurt cultures?
Does temperature affect how long blood can be stored?
How does moisture affect the growth of moss on a tree?
Which of Leeuwenhoek’s microscopes was the coolest?

Explain the relationship between forward and backward reactions in equilibrium, and predict how changing the amount of a reactant (creating a tension) will affect that relationship.

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next

Which of the following words describe the reality that the universe looks the same from various perspective