如圖,點(diǎn)A,B,C是數(shù)軸上三點(diǎn),點(diǎn)C表示的數(shù)為6,BC=4,AB=12.
(1)寫出數(shù)軸上點(diǎn)A表示的數(shù):
-10
-10
;
(2)動(dòng)點(diǎn)P,Q同時(shí)從A,C出發(fā),點(diǎn)P以每秒4個(gè)單位長(zhǎng)度的速度沿?cái)?shù)軸向右勻速運(yùn)動(dòng),點(diǎn)Q以每秒2個(gè)單位長(zhǎng)度的速度沿?cái)?shù)軸向左勻速運(yùn)動(dòng),設(shè)運(yùn)動(dòng)時(shí)間為t(t>0)秒.
①當(dāng)t=2時(shí),求出此時(shí)P,Q在數(shù)軸上表示的數(shù);
②t為何值時(shí),點(diǎn)P,Q相距2個(gè)單位長(zhǎng)度,并寫出此時(shí)點(diǎn)P,Q在數(shù)軸上表示的數(shù).