You are now a sqlite data analyst, and you are given a database schema as follows:

    【Schema】
    【DB_ID】 car_retails
【Schema】
# Table: products
[
(productCode:TEXT, Primary Key, Examples: [S10_1678, S10_1949, S10_2016]),
(productName:TEXT, Examples: [1969 Harley Davidson Ultimate Chopper]),
(productLine:TEXT, Examples: [Motorcycles, Classic Cars, Trucks and Buses]),
(productScale:TEXT, Examples: [1:10, 1:12, 1:18]),
(productVendor:TEXT, Examples: [Min Lin Diecast]),
(productDescription:TEXT),
(quantityInStock:INTEGER, Examples: [7933, 7305, 6625]),
(buyPrice:REAL, Examples: [48.81, 98.58, 68.99]),
(MSRP:REAL, Examples: [95.7, 214.3, 118.94])
]
# Table: orderdetails
[
(orderNumber:INTEGER, Primary Key, Examples: [10100, 10101, 10102]),
(productCode:TEXT, Primary Key, Examples: [S18_1749, S18_2248, S18_4409]),
(quantityOrdered:INTEGER, Examples: [30, 50, 22]),
(priceEach:REAL, Examples: [136.0, 55.09, 75.46]),
(orderLineNumber:INTEGER, Examples: [3, 2, 4])
]
# Table: payments
[
(customerNumber:INTEGER, Primary Key, Examples: [103, 112, 114]),
(checkNumber:TEXT, Primary Key, Examples: [HQ336336, JM555205, OM314933]),
(paymentDate:DATE, Examples: [2004-10-19]),
(amount:REAL, Examples: [6066.78, 14571.44, 1676.14])
]
# Table: orders
[
(orderNumber:INTEGER, Primary Key, Examples: [10100, 10101, 10102]),
(orderDate:DATE, Examples: [2003-01-06]),
(requiredDate:DATE, Examples: [2003-01-13]),
(shippedDate:DATE, Examples: [2003-01-10]),
(status:TEXT, Examples: [Shipped, Resolved, Cancelled]),
(comments:TEXT),
(customerNumber:INTEGER, Examples: [363, 128, 181])
]
# Table: productlines
[
(productLine:TEXT, Primary Key, Examples: [Classic Cars, Motorcycles, Planes]),
(textDescription:TEXT),
(htmlDescription:TEXT),
(image:BLOB)
]
# Table: employees
[
(employeeNumber:INTEGER, Primary Key, Examples: [1002, 1056, 1076]),
(lastName:TEXT, Examples: [Murphy, Patterson, Firrelli]),
(firstName:TEXT, Examples: [Diane, Mary, Jeff]),
(extension:TEXT, Examples: [x5800, x4611, x9273]),
(email:TEXT),
(officeCode:TEXT, Examples: [1, 6, 4]),
(reportsTo:INTEGER, Examples: [1002, 1056, 1143]),
(jobTitle:TEXT, Examples: [President, VP Sales, VP Marketing])
]
# Table: offices
[
(officeCode:TEXT, Primary Key, Examples: [1, 2, 3]),
(city:TEXT, Examples: [San Francisco, Boston, NYC]),
(phone:TEXT, Examples: [+1 650 219 4782, +1 215 837 0825, +1 212 555 3000]),
(addressLine1:TEXT, Examples: [100 Market Street, 1550 Court Place, 523 East 53rd Street]),
(addressLine2:TEXT, Examples: [Suite 300, Suite 102, apt. 5A]),
(state:TEXT, Examples: [CA, MA, NY]),
(country:TEXT, Examples: [USA, France, Japan]),
(postalCode:TEXT, Examples: [94080, 02107, 10022]),
(territory:TEXT, Examples: [NA, EMEA, Japan])
]
# Table: customers
[
(customerNumber:INTEGER, Primary Key, Examples: [103, 112, 114]),
(customerName:TEXT, Examples: [Atelier graphique]),
(contactLastName:TEXT, Examples: [Schmitt, King, Ferguson]),
(contactFirstName:TEXT, Examples: [Carine , Jean, Peter]),
(phone:TEXT, Examples: [40.32.2555, 7025551838, 03 9520 4555]),
(addressLine1:TEXT, Examples: [54, rue Royale, 8489 Strong St., 636 St Kilda Road]),
(addressLine2:TEXT, Examples: [Level 3]),
(city:TEXT, Examples: [Nantes, Las Vegas, Melbourne]),
(state:TEXT, Examples: [NV, Victoria, CA]),
(postalCode:TEXT, Examples: [44000, 83030, 3004]),
(country:TEXT, Examples: [France, USA, Australia]),
(salesRepEmployeeNumber:INTEGER, Examples: [1370, 1166, 1611]),
(creditLimit:REAL, Examples: [21000.0, 71800.0, 117300.0])
]
【Foreign keys】
products.productLine=productlines.productLine
orderdetails.productCode=products.productCode
orderdetails.orderNumber=orders.orderNumber
payments.customerNumber=customers.customerNumber
orders.customerNumber=customers.customerNumber
employees.officeCode=offices.officeCode
employees.reportsTo=employees.employeeNumber
customers.salesRepEmployeeNumber=employees.employeeNumber

    【Question】
    If I'm from the Muscle Machine Inc, to which e-mail adress should I write a letter if I want to reach the superior of my sales representitive? Muscle Machine Inc is name of customer; superior refers to 'reportsTO', who is the leader of the 'employeeNumber'

    【Evidence】
    Muscle Machine Inc is name of customer; superior refers to 'reportsTO', who is the leader of the 'employeeNumber'

    Please read and understand the database schema carefully, and generate an executable SQL based on the user's question and evidence. 

SQL: SELECT t2.email FROM customers AS t1 INNER JOIN employees AS t2 ON t1.salesRepEmployeeNumber = t2.employeeNumber WHERE t1.customerName = 'Muscle Machine Inc'