$\text{ATP}$ase is located in $:-$

Which of the following statements are correct regarding skeletal muscle?
$A$. Muscle bundles are held together by a collagenous connective tissue layer called fascicle.
$B$. Sarcoplasmic reticulum of muscle fibre is a storehouse of calcium ions.
$C$. Striated appearance of skeletal muscle fibre is due to the distribution pattern of actin and myosin proteins.
$D$. $M$ line is considered as the functional unit of contraction called sarcomere.
Choose the most appropriate answer from the options given below:

Which of the following activities occurs at the site labeled $P$ in the given diagram of a myosin monomer?

$ATP_{ase}$ activity is found in:

Hypertrophy of muscle is

What is the location of troponin in the process of muscle contraction?