I just... I don't know man I suck at physics :( A tour guide shouts across a canyon. At a temperature of 20 °C, her echo is heard 2.00 s later. How wide is the canyon?

The answer is 340 m I just don't know how to get that

An astronaut floating in space is trying to use her jetpack to get back to her space station, but she is being pulled away by a nearby planet, as shown in the image below. her jetpack provides a constant thrust of 310 n. if she angles her jetpack in such a way that it cancels out the vertical force due to the planet's gravity, what is her net horizontal force? thaud 487 o a. 54.8 n toward the space station o b. 212.9 n toward the space station o c. 185.2 n toward the space station o d 956 n toward the space station