A winery has a vault with two pipes leading to it. The inlet pipe can fill the vat in 7 hours, while the outlet pipe can empty it in 9 hours. How long will it take to fill the vat if both pipes are left open?

Can someone answer it, and plot it, for 20 points and brainliest answer? p.s. they're the same ! : )

The tiles below are pieces of a normal ecg tracing representing a little less than two heartbeats at a resting rate of 80 bpm. arrange the tiles in their correct order. rank from first to last. do not overlap any tiles.

In the diagram below? p is circumscribed about quadrilateral abcd. what is the value of x