1.our physical state can affect our mental and emotional health
true or false

2. to be effective, exercise must reach at least
a.40%
b.60%
c.80%

3. the heart is the center of physical fitness
true or false

4.it is okay for adolescents to lift heavy weights
true or false

5. participating in aerobic exercise develops muscular endurance
true or false

6.aerobic means "without oxygen "
true or false