7. An object falls from a great height. It is known that the distance it falls in the first second is $\mathbf{5}$ meters, and the distance it falls each subsequent second is 10 meters more than the previous second. The object reaches the ground at the end of 10 seconds. Therefore, the initial height of the object above the ground is $\qquad$ meters.
【Answer】500
Analysis: $5+15+25+\ldots \ldots+95=(5+95) \times 10 \div 2=500$