Find an exact value.

cosine of nineteen pi divided by twelve.

quantity square root of six minus square root of two divided by four.

quantity square root of six plus square root of two divided by four.

quantity negative square root of six minus square root of two divided by four.

quantity square root of two minus square root of six divided by four.

the answer is the third / last answer

step-by-step explanation:

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.

step-by-step explanation: