2026年3月国际C卷 · 第 2 题

2026年3月国际C卷 · 原库模块 2 · Q2 原库参考解析

Sunspots are temporary dark spots on the surface of the Sun. The monthly mean number of sunspots for a calendar month is the average of the number of sunspots observed each day during the month. The linear function s models the monthly mean number of sunspots as a function of the number of months, x, since December 2013, where \( 0\le x\le30 \) . The graph of \( y=sx \) is shown.

Which of the following is the best estimate for the monthly mean number of sunspots in December 2014?