A.防疫道路千万条,接种疫苗第一条;
B.疫苗接种保安全,战胜新冠靠全员;
C.接种疫苗别再拖,安全保障好处多;
D.疫苗接种连万家,平安健康乐全家.
志愿者小张和小李利用休息时间到某小区张贴海报.
(1)小张从一套海报中随机抽取一张,抽到B海报的概率是 .
(2)小张和小李从同一套海报中各随机抽取一张,用列表法或画树状图法,求他们两个人中有一个人抽到D海报的概率.
同类型试题
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2