[填空题]
After solving a problem, John has an exact mcacpbla ak5a ;+)o9art(-,zansw6 fko 6n p/uy(r0f n:id39qyxo 6q-yuker of z=0.1475.
1.Write down the exact value of z in the form a×10$^k$ , where 1≤a<10,k∈Z.
The number= ×10$^{-1}$.
2.State the value of z given correct to 2 significant figures.
The number= .
3.Calculate the percentage error if z is given correct to 2 significant figures.
Using the percentage error formula ϵ= %.