1. Write the value (in decimal fraction) and the place value of each of the underlined digits. *a) Number: $2,\underline{3}45$ Place value: Hundreds Number value: $300$ *b) Number: $4,67\underline{8}$ Place value: Units Number value: $8$ *c) Number: $1,\underline{9}53$ Place value: Hundreds Number value: $900$ *d) Number: $564,\underline{3}4$ Place value: Tenths Number value: $0.3$ or $\frac{3}{10}$ 2. Write down the values of the points marked A to D using decimal fractions. The number line is divided into tenths between $6.4$ and $6.5$. Each small mark represents $0.01$. A: $6.4 + 3 \times 0.01 = 6.4 + 0.03 = \boxed{6.43}$ B: $6.4 + 7 \times 0.01 = 6.4 + 0.07 = \boxed{6.47}$ C: This point is explicitly marked as $\boxed{6.5}$ D: $6.5 + 5 \times 0.01 = 6.5 + 0.05 = \boxed{6.55}$