Answer:
Muscles work in pairs to move a bone.
Skeletal muscles only PULL in one direction. For this reason they always come in pairs. When one muscle in a pair contracts, to bend a joint for example, its counterpart then contracts and pulls in the opposite direction to straighten the joint out again.
Answer:
His map of the ocean floor did not support his theory
Explanation:
- Alfred Wegner was a great scientist
- He observed the plate tectonics of earth and described it in a theory.
- It was dismissed after viewing his ocean floor
Answer: Cornea
Explanation: The cornea is the only part of a human body that has no blood supply as it gets oxygen directly through the air.
Answer:
The correct option is C
Explanation:
From the question we are told that
The reaction is

Generally
Here
is the change in enthalpy
is the change in the internal energy
is the difference between that number of moles of product and the number of moles of reactant
Looking at the reaction we can discover that the elements that was consumed and the element that was formed is
and
and this are both gases so the change would occur in the number of moles
So
The negative sign in the equation tell us that the enthalpy
would be less than the Internal energy 
2 Cr + 3 Cl2 ------> 2CrCl3