阅读理解
Visiting Joshua Tree National Park, California
Joshua Tree National Park is nearly 800,000 acres (英亩) large and surrounds parts of the Mojave and Colorado Deserts in South-central California. Although barren at first sight, the park is full of wildlife and provides a variety of entertainment activities from hiking to climbing. Within a three-hour drive, Joshua Tree National Park takes at least a full day to visit.
Things to do
Hiking opportunities within the park include several choices, from 12 self-guided nature routines to all-day back-country hikes.
Joshua Tree NP has nine camping grounds, and back-country camping is also allowed.
Rock climbing is a popular activity in the park, which has 10 mountains greater than 5, 000 feet in height.
When to visit
Joshua Tree NP is open 365 days a year, although the best time to visit is October through April, when temperature is milder. The peak season is when the wild flowers bloom, and the summer months are the least crowded.
What to bring
In addition to your camera and telescope, be sure to carry lots of water. Park and guiding maps can be picked up at any of the three visitor centers.
Fees
Parking fees: You can buy a seven-day vehicle permit (周票) for $ 15, a single entry permit for $ 5, or Joshua Tree National Park annual (每年的) pass for $ 60.
Camping fees: They vary by camping ground
Ag+(aq)+Cl-(aq)在水中的沉淀溶解平衡曲线如图所示。下列说法正确的是 （ ）