Given the recursive formula for the arithmetic sequence \( a_{1}=-5, a_{n}=a_{n-1}+4 \), find the first three terms of the sequence. ( 2 points) \( a_{1}=\square, a_{2}=\square \), and \( a_{3}= \)

A certain radioactive substance has a half-life of 10 years. If you start with 80 grams, how much will remain after 30 years?

3. Primi e perfetti a. Qui di seguito sono riportati alcuni numeri scomposti in fattori primi. Quali tra essi sono quadrati perfetti? Motiva la risposta. \( \begin{array}{ll}192=2^{6} \times 3 & \text { (si) (NO) } \\ 484=2^{2} \times 11^{2} & \text { (si) (NO } \\ 200=2^{3} \times 5^{2} & \text { (i) (NO } \\ 144=2^{4} \times 3^{2} & \text { (si) (NO) }\end{array} \)

The absolute value of a real number \( x \) is represented by:

The value of \( \sqrt{10+\sqrt{25+\sqrt{108+\sqrt{154+\sqrt{225}}}}} \) is

25. Expresa en la forma radical \( y \) halla el resultado Potencia con exponente fraccionario \( \begin{array}{lll}\text { a) } 64^{\frac{1}{2}} & \text { b) }(-125)^{-\frac{1}{3}} & \text { c) }\left(256 x^{3} y^{2}\right)^{\frac{4}{7}}\end{array} \)