[多选题]消防“一懂三会”的“三会”是指（ ）。
A.懂得本场所火灾危险性
B.会报警
C.会扑救初期火灾
D.会逃生自救

{{B}}Questions 47 to 56 are based on the following passage.{{/B}}
California has more than two thousand{{U}} (47) {{/U}}of plants that are not found anywhere else. A new study says climate change could severely{{U}} (48) {{/U}}these plants by the end of the century. Many could move northward and toward the Pacific coast in reaction to rising temperatures and {{U}} (49) {{/U}}in rainfall. Others might climb up mountains to find the cooler climates they like.
But David Akeley at the University of California, Berkeley, says the{{U}} (50) {{/U}}of climate change is greater than during ice ages in the past. He says plants that cannot move fast enough are in
{{U}} (51) {{/U}}of getting killed off before they can relocate. Changes in plants could also affect animals that depend on the plants for food.
About forty percent of all{{U}} (52) {{/U}}plants in California are endemic, meaning that they are found only in that state