Solve the following reliability problems:

a) A given component has an MTBF of 105hr, what is the reliability for an operating period of 10 hr for 6 such components in series?

b) Four capacitances of 25 MF each are connected in parallel to act as a single capacitance of 100MF required for the successful operation of a unit. If the reliability of these capacitors are 0.6, 0.7,0.8 and 0.9 respectively , find the reliability of the unit