1)-3a(a²+2ab-5b) 2)(4y²-2y³+16)•(-2,5y) 3)0,3mn(2mn²-4m²n+3mn)

Let's break down and simplify each expression step by step.

1) \(-3a(a² + 2ab - 5b)\)

To simplify this expression, distribute \(-3a\) across each term in the parentheses:

\[ -3a(a²) + (-3a)(2ab) + (-3a)(-5b) \]

Calculating each term:

1. \(-3a(a²) = -3a^3\)
2. \(-3a(2ab) = -6a^2b\)
3. \(-3a(-5b) = 15ab\)

Putting it all together, we get:

\[ -3a^3 - 6a^2b + 15ab \]

So, the simplified expression is:

\[ -3a^3 - 6a^2b + 15ab \]

2) \((4y² - 2y³ + 16)(-2.5y)\)

Now, we will distribute \(-2.5y\) across each term in the polynomial:

\[ -2.5y(4y^2) + (-2.5y)(-2y^3) + (-2.5y)(16) \]

Calculating each term:

1. \(-2.5y(4y^2) = -10y^3\)
2. \(-2.5y(-2y^3) = 5y^4\)
3. \(-2.5y(16) = -40y\)

Now, combining these results, we have:

\[ 5y^4 - 10y^3 - 40y \]

So, the simplified expression is:

\[ 5y^4 - 10y^3 - 40y \]

3) \(0.3mn(2mn^2 - 4m^2n + 3mn)\)

Again, we'll distribute \(0.3mn\) across each term:

\[ 0.3mn(2mn^2) + 0.3mn(-4m^2n) + 0.3mn(3mn) \]

Calculating each term:

1. \(0.3mn(2mn^2) = 0.6m^2n^3\)
2. \(0.3mn(-4m^2n) = -1.2m^3n^2\)
3. \(0.3mn(3mn) = 0.9m^2n^2\)

Putting it all together, we have:

\[ 0.6m^2n^3 - 1.2m^3n^2 + 0.9m^2n^2 \]

You can combine the like terms \(-1.2m^3n^2 + 0.9m^2n^2\) if needed, but they are not like terms so the expression remains:

Thus, the simplified expression is:

\[ 0.6m^2n^3 - 1.2m^3n^2 + 0.9m^2n^2 \]

Summary of Simplified Expressions

1. \(-3a^3 - 6a^2b + 15ab\)
2. \(5y^4 - 10y^3 - 40y\)
3. \(0.6m^2n^3 - 1.2m^3n^2 + 0.9m^2n^2\)

If you have any further questions or need additional help, feel free to ask!