はい、基本的な数学演算を伴うテキスト入力に対応するようにプログラムを更新することができます。以下に実装例を示す：

```python 
class Calculator:
def init(self):
pass

def evaluate(self, expression):
    tokens = expression.split()
    stack = []
    i = 0
    while i < len(tokens):
        if tokens[i].isdigit():
            stack.append(float(tokens[i]))
        else:
            if tokens[i] == '+':
                a = stack.pop()
                b = stack.pop()
                stack.append(a + b)
            elif tokens[i] == '-':
                a = stack.pop()
                b = stack.pop()
                stack.append(b - a)
            elif tokens[i] == '*':
                a = stack.pop()
                b = stack.pop()
                stack.append(a * b)
            elif tokens[i] == '/':
                a = stack.pop()
                b = stack.pop()
                stack.append(b / a)
        i += 1
    return stack.pop()
```

**使用例
```python
c = Calculator()
print(c.evaluate('2 + 10 / 5')) # Output: 4.0
print(c.evaluate('3 * 9 - 7')) # Output: 20.0
```
Yes, we can update the program to work on text input with basic mathematical operations. Here's an example implementation:

```python 
class Calculator:
def init(self):
pass

def evaluate(self, expression):
    tokens = expression.split()
    stack = []
    i = 0
    while i < len(tokens):
        if tokens[i].isdigit():
            stack.append(float(tokens[i]))
        else:
            if tokens[i] == '+':
                a = stack.pop()
                b = stack.pop()
                stack.append(a + b)
            elif tokens[i] == '-':
                a = stack.pop()
                b = stack.pop()
                stack.append(b - a)
            elif tokens[i] == '*':
                a = stack.pop()
                b = stack.pop()
                stack.append(a * b)
            elif tokens[i] == '/':
                a = stack.pop()
                b = stack.pop()
                stack.append(b / a)
        i += 1
    return stack.pop()
```

**Example usage:**
```python
c = Calculator()
print(c.evaluate('2 + 10 / 5')) # Output: 4.0
print(c.evaluate('3 * 9 - 7')) # Output: 20.0
```