What is a public key infrastructure? select one: a. a structure that provides all of the components needed for entities to communicate securely and in a predictable manner b. a structure that enables secure communications in chat rooms, instant messaging, and text messaging c. is a method of securing communications through the use of a single shared key d. a structure that enables parties to use communications such as email?

Stephen barrett,md previous writing experience ?

Zeta corporation is a manufacturer of sports caps, which require soft fabric. the standards for each cap allow 2.00 yards of soft fabric, at a cost of $2.00 per yard. during the month of january, the company purchased 25,000 yards of soft fabric at $2.10 per yard, to produce 12,000 caps. what is zeta corporation's materials price variance for the month of january?

The usa today reports that the average expenditure on valentine's day is $100.89. do male and female consumers differ in the amounts they spend? the average expenditure in a sample survey of 47 male consumers was $135.67, and the average expenditure in a sample survey of 38 female consumers was $68.64. based on past surveys, the standard deviation for male consumers is assumed to be $34, and the standard deviation for female consumers is assumed to be $17.