Answer: The unit circle contains values for sine, cosine, and tangent.
Step-by-step explanation: The coordinates on the unit circle are the sine ratio and cosine ratio. From this, the tangent, secant, cosecant, and cotangent can be found.
A I am pretty sure. I apologize if I am incorrect.
For this case we must simplify the following expression:

We must add similar terms taking into account that:
- Equal signs are added and the same sign is placed.
- Different signs are subtracted and the major sign is placed.

Thus, the simplified expression is:

Answer:

1647. 1 hour=60 minutes. John can mow 247 square feet per minute, so he can mow 60*247=14820 square feet per hour. 1 yard=3 feet, so 1 square yard =3^2=9 square feet, so in the same duration of time, John can mow 14820/9=1647 square yards (approximately) per hour.